(1) Field of the Invention
The present invention relates to a liquid crystal display device.
(2) Related Art Statement
In recent years, the use of light emitting type plasma display devices and non-light emitting type liquid crystal display devices has become more widespread instead of CRT's (cathode ray tubes).
From among these, liquid crystal display devices use liquid crystal panels as transmission type light modulation elements, and illumination devices (hereinafter referred to as backlight) are provided on the rear surface of the liquid crystal panels so that the liquid crystal panels are irradiated with light. In addition, the transmittance of light from the backlight is controlled in the liquid crystal panels so that an image is formed.
Liquid crystal display devices have one characteristic in that they can be thinly formed in comparison with CRT's, and in recent years, a thinner liquid crystal display device has been desired. Therefore, it has been requested to reduce the depth of the backlight that forms the liquid crystal display device. A backlight using EEFL's (external electrode fluorescent lamps) is disclosed in accordance with a technology relating to the backlight of such a liquid crystal display device in Patent Document 1, for example.
[Patent Document 1] Japanese Unexamined Patent Publication 2007-184232 (see Paragraph 0052)
EEFL's and CCFL's (cold cathode fluorescent lamps) are fluorescent lamps formed of long, thin tubes, and therefore a thin backlight can be provided using fluorescent lamps, such as EEFL's or CCFL's.
In sufficiently thin backlights (thickness is approximately ⅔ to ½) in comparison with conventional backlights, the fluorescent lamps are affected by heat emitting bodies, such as circuits, on the rear side of the backlight so that the inconsistency in temperature becomes greater in the longitudinal direction of the fluorescent lamps, and in some cases the emission of light becomes inconsistent.